How this calculator works
Dilution conserves the number of cells in the withdrawn stock aliquot. Final volume includes the aliquot and the added medium. Both concentration inputs use cells per mL; volume selectors may differ because the calculator converts them to the same base unit. This model assumes no growth, loss, aggregation or change in viability during preparation.
Formula
C1 × V1 = C2 × V2. Stock volume V1 = C2V2/C1. Added medium = V2 - V1. Dilution factor = V2/V1 = C1/C2.
Worked example
To make 10 mL at 100,000 cells/mL from 1,000,000 cells/mL stock, take 1 mL stock and add 9 mL medium. A 2 mL aliquot at 500,000 cells/mL made up to 20 mL gives 50,000 cells/mL.
Advertisement
Frequently asked questions
Is final volume the volume of medium to add?
No. Final volume is stock plus medium. The separate diluent output shows how much medium to add.
Can this prepare a higher concentration?
No. Removing medium or concentrating cells needs a different operation. This calculator rejects results that would require a negative amount of diluent.
Should I use total or viable cells?
Use the same basis for stock and target. If the target is viable cells per mL, measure the viable stock concentration.